You will find more info on the Mercruiser forum, than here on the mercury outboard forum. That being said, I've owned several boats with mercruiser 470s, and always liked those engines. They were rugged, economical, and reliable, but had some unique quirks of their own. One was that the water pump was on end of camshaft, and seal between pump and internal engine would wear a a groove in camshaft causing water to enter engine. There is a repair sleeve kit available to repair. Another frequent problem was magnets in generator/alternator on front end of crankshaft would come loose causing damage. An aftermarket regular type alternator takes care of this. These engines were considered half of a Ford 460 engine, and used some parts from that Ford engine. Keeping clean oil & filter, regular tuneup items, plus being sure lower unit has oil and lower water pump is working correctly are important to watch. recommend that you get a repair manual for this I/o, and follow it's guidelines.
